diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 38115beec6988fa94a68709c4710486ca796beb7..7e4f1a02646e1218cccb5bf6e4b82bd858979110 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -38,7 +38,7 @@ workflow:
       when: never
     # For merge requests, create a pipeline.
     - if: '$CI_MERGE_REQUEST_IID'
-    # For `master` branch, create a pipeline (this includes on schedules, pushes, merges, etc.).
+    # For `$CI_DEFAULT_BRANCH` branch, create a pipeline (this includes on schedules, pushes, merges, etc.).
     - if: '$CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH'
     # For tags, create a pipeline.
     - if: '$CI_COMMIT_TAG'
diff --git a/.gitlab/ci/cache-repo.gitlab-ci.yml b/.gitlab/ci/cache-repo.gitlab-ci.yml
index 5a4f20eed4149f2c15c29d6ff88b2e1863b2ce5e..6671c2f9e3ae803e68b590fd8afcacef1289ba96 100644
--- a/.gitlab/ci/cache-repo.gitlab-ci.yml
+++ b/.gitlab/ci/cache-repo.gitlab-ci.yml
@@ -1,4 +1,4 @@
-# Builds a cached .tar.gz of the master branch with full history and
+# Builds a cached .tar.gz of the $CI_DEFAULT_BRANCH branch with full history and
 # uploads it to Google Cloud Storage. This archive is downloaded by a
 # script defined by a CI/CD variable named CI_PRE_CLONE_SCRIPT. This has
 # two benefits:
diff --git a/.gitlab/ci/frontend.gitlab-ci.yml b/.gitlab/ci/frontend.gitlab-ci.yml
index 910a58bcd0eb19c0179d2b15a441794b91ffcded..e739b046ff79e0ffcf30d6eb0590cf89df8225ba 100644
--- a/.gitlab/ci/frontend.gitlab-ci.yml
+++ b/.gitlab/ci/frontend.gitlab-ci.yml
@@ -246,7 +246,7 @@ coverage-frontend:
   extends:
     - .default-retry
     - .yarn-cache
-    - .frontend:rules:ee-mr-and-master-only
+    - .frontend:rules:ee-mr-and-default-branch-only
   needs: ["jest"]
   stage: post-test
   before_script:
diff --git a/.gitlab/ci/rails.gitlab-ci.yml b/.gitlab/ci/rails.gitlab-ci.yml
index f4ea6e3ae013701020e9a730dc0e5536928ea5ac..6b5c617dccc85c2b91257a7456536f2097aa3eb1 100644
--- a/.gitlab/ci/rails.gitlab-ci.yml
+++ b/.gitlab/ci/rails.gitlab-ci.yml
@@ -142,7 +142,7 @@
 ############################
 
 #######################################################
-# EE/FOSS: default refs (MRs, master, schedules) jobs #
+# EE/FOSS: default refs (MRs, default branch, schedules) jobs #
 setup-test-env:
   extends:
     - .rails-job-base
@@ -347,7 +347,7 @@ db:migrate:reset:
 db:check-schema:
   extends:
     - .db-job-base
-    - .rails:rules:ee-mr-and-master-only
+    - .rails:rules:ee-mr-and-default-branch-only
   script:
     - source scripts/schema_changed.sh
 
@@ -538,11 +538,11 @@ rspec:feature-flags:
         run_timed_command "bundle exec scripts/used-feature-flags";
       fi
 
-# EE/FOSS: default refs (MRs, master, schedules) jobs #
+# EE/FOSS: default refs (MRs, default branch, schedules) jobs #
 #######################################################
 
 ##################################################
-# EE: default refs (MRs, master, schedules) jobs #
+# EE: default refs (MRs, default branch, schedules) jobs #
 rspec migration pg11-as-if-foss:
   extends:
     - .rspec-base-pg11-as-if-foss
@@ -685,81 +685,81 @@ db:rollback geo:
   script:
     - bundle exec rake geo:db:migrate VERSION=20170627195211
     - bundle exec rake geo:db:migrate
-# EE: default refs (MRs, master, schedules) jobs #
+# EE: default refs (MRs, default branch, schedules) jobs #
 ##################################################
 
 ##########################################
-# EE/FOSS: master nightly scheduled jobs #
+# EE/FOSS: default branch nightly scheduled jobs #
 rspec migration pg12:
   extends:
     - .rspec-base-pg12
     - .rspec-base-migration
-    - .rails:rules:master-schedule-nightly--code-backstage
+    - .rails:rules:default-branch-schedule-nightly--code-backstage
     - .rspec-migration-parallel
 
 rspec unit pg12:
   extends:
     - .rspec-base-pg12
-    - .rails:rules:master-schedule-nightly--code-backstage
+    - .rails:rules:default-branch-schedule-nightly--code-backstage
     - .rspec-unit-parallel
 
 rspec integration pg12:
   extends:
     - .rspec-base-pg12
-    - .rails:rules:master-schedule-nightly--code-backstage
+    - .rails:rules:default-branch-schedule-nightly--code-backstage
     - .rspec-integration-parallel
 
 rspec system pg12:
   extends:
     - .rspec-base-pg12
-    - .rails:rules:master-schedule-nightly--code-backstage
+    - .rails:rules:default-branch-schedule-nightly--code-backstage
     - .rspec-system-parallel
-# EE/FOSS: master nightly scheduled jobs #
+# EE/FOSS: default branch nightly scheduled jobs #
 ##########################################
 
 #####################################
-# EE: master nightly scheduled jobs #
+# EE: default branch nightly scheduled jobs #
 rspec-ee migration pg12:
   extends:
     - .rspec-ee-base-pg12
     - .rspec-base-migration
-    - .rails:rules:master-schedule-nightly--code-backstage-ee-only
+    - .rails:rules:default-branch-schedule-nightly--code-backstage-ee-only
     - .rspec-ee-migration-parallel
 
 rspec-ee unit pg12:
   extends:
     - .rspec-ee-base-pg12
-    - .rails:rules:master-schedule-nightly--code-backstage-ee-only
+    - .rails:rules:default-branch-schedule-nightly--code-backstage-ee-only
     - .rspec-ee-unit-parallel
 
 rspec-ee integration pg12:
   extends:
     - .rspec-ee-base-pg12
-    - .rails:rules:master-schedule-nightly--code-backstage-ee-only
+    - .rails:rules:default-branch-schedule-nightly--code-backstage-ee-only
     - .rspec-ee-integration-parallel
 
 rspec-ee system pg12:
   extends:
     - .rspec-ee-base-pg12
-    - .rails:rules:master-schedule-nightly--code-backstage-ee-only
+    - .rails:rules:default-branch-schedule-nightly--code-backstage-ee-only
     - .rspec-ee-system-parallel
 
 rspec-ee unit pg12 geo:
   extends:
     - .rspec-ee-base-geo-pg12
-    - .rails:rules:master-schedule-nightly--code-backstage-ee-only
+    - .rails:rules:default-branch-schedule-nightly--code-backstage-ee-only
     - .rspec-ee-unit-geo-parallel
 
 rspec-ee integration pg12 geo:
   extends:
     - .rspec-ee-base-geo-pg12
-    - .rails:rules:master-schedule-nightly--code-backstage-ee-only
+    - .rails:rules:default-branch-schedule-nightly--code-backstage-ee-only
 
 rspec-ee system pg12 geo:
   extends:
     - .rspec-ee-base-geo-pg12
-    - .rails:rules:master-schedule-nightly--code-backstage-ee-only
-# EE: master nightly scheduled jobs #
+    - .rails:rules:default-branch-schedule-nightly--code-backstage-ee-only
+# EE: default branch nightly scheduled jobs #
 #####################################
 
 ##################################################
diff --git a/.gitlab/ci/rules.gitlab-ci.yml b/.gitlab/ci/rules.gitlab-ci.yml
index b8b37c530f2540c8227774c51dbd11af1e1945a4..79c0745d864cb2d129ab2e16449c0c51df4f16fc 100644
--- a/.gitlab/ci/rules.gitlab-ci.yml
+++ b/.gitlab/ci/rules.gitlab-ci.yml
@@ -11,25 +11,25 @@
   if: '$CI_PROJECT_NAME != "gitlab-foss" && $CI_PROJECT_NAME != "gitlab-ce" && $CI_PROJECT_NAME != "gitlabhq"'
 
 .if-default-refs: &if-default-refs
-  if: '$CI_COMMIT_REF_NAME == "master" || $CI_COMMIT_REF_NAME == "main" || $CI_COMMIT_REF_NAME =~ /^[\d-]+-stable(-ee)?$/ || $CI_COMMIT_REF_NAME =~ /^\d+-\d+-auto-deploy-\d+$/ || $CI_COMMIT_REF_NAME =~ /^security\// || $CI_MERGE_REQUEST_IID || $CI_COMMIT_TAG || $FORCE_GITLAB_CI'
+  if: '$CI_COMMIT_REF_NAME == $CI_DEFAULT_BRANCH || $CI_COMMIT_REF_NAME =~ /^[\d-]+-stable(-ee)?$/ || $CI_COMMIT_REF_NAME =~ /^\d+-\d+-auto-deploy-\d+$/ || $CI_COMMIT_REF_NAME =~ /^security\// || $CI_MERGE_REQUEST_IID || $CI_COMMIT_TAG || $FORCE_GITLAB_CI'
 
-.if-master-refs: &if-master-refs
-  if: '$CI_COMMIT_REF_NAME == "master" || $CI_COMMIT_REF_NAME == "main"'
+.if-default-branch-refs: &if-default-branch-refs
+  if: '$CI_COMMIT_REF_NAME == $CI_DEFAULT_BRANCH'
 
-.if-master-push: &if-master-push
-  if: '($CI_COMMIT_BRANCH == "master" || $CI_COMMIT_REF_NAME == "main") && $CI_PIPELINE_SOURCE == "push"'
+.if-default-branch-push: &if-default-branch-push
+  if: '$CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH && $CI_PIPELINE_SOURCE == "push"'
 
-.if-master-schedule-2-hourly: &if-master-schedule-2-hourly
-  if: '($CI_COMMIT_BRANCH == "master" || $CI_COMMIT_REF_NAME == "main") && $CI_PIPELINE_SOURCE == "schedule" && $FREQUENCY == "2-hourly"'
+.if-default-branch-schedule-2-hourly: &if-default-branch-schedule-2-hourly
+  if: '$CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH && $CI_PIPELINE_SOURCE == "schedule" && $FREQUENCY == "2-hourly"'
 
-.if-master-schedule-nightly: &if-master-schedule-nightly
-  if: '($CI_COMMIT_BRANCH == "master" || $CI_COMMIT_REF_NAME == "main") && $CI_PIPELINE_SOURCE == "schedule" && $FREQUENCY == "nightly"'
+.if-default-branch-schedule-nightly: &if-default-branch-schedule-nightly
+  if: '$CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH && $CI_PIPELINE_SOURCE == "schedule" && $FREQUENCY == "nightly"'
 
 .if-auto-deploy-branches: &if-auto-deploy-branches
   if: '$CI_COMMIT_BRANCH =~ /^\d+-\d+-auto-deploy-\d+$/'
 
-.if-master-or-tag: &if-master-or-tag
-  if: '$CI_COMMIT_REF_NAME == "master" || $CI_COMMIT_REF_NAME == "main" || $CI_COMMIT_TAG'
+.if-default-branch-or-tag: &if-default-branch-or-tag
+  if: '$CI_COMMIT_REF_NAME == $CI_DEFAULT_BRANCH || $CI_COMMIT_TAG'
 
 .if-merge-request: &if-merge-request
   if: '$CI_MERGE_REQUEST_IID'
@@ -52,8 +52,8 @@
 .if-dot-com-gitlab-org-schedule: &if-dot-com-gitlab-org-schedule
   if: '$CI_SERVER_HOST == "gitlab.com" && $CI_PROJECT_NAMESPACE == "gitlab-org" && $CI_PIPELINE_SOURCE == "schedule"'
 
-.if-dot-com-gitlab-org-master: &if-dot-com-gitlab-org-master
-  if: '$CI_SERVER_HOST == "gitlab.com" && $CI_PROJECT_NAMESPACE == "gitlab-org" && ($CI_COMMIT_REF_NAME == "master" || $CI_COMMIT_REF_NAME == "main")'
+.if-dot-com-gitlab-org-default-branch: &if-dot-com-gitlab-org-default-branch
+  if: '$CI_SERVER_HOST == "gitlab.com" && $CI_PROJECT_NAMESPACE == "gitlab-org" && $CI_COMMIT_REF_NAME == $CI_DEFAULT_BRANCH'
 
 .if-dot-com-gitlab-org-merge-request: &if-dot-com-gitlab-org-merge-request
   if: '$CI_SERVER_HOST == "gitlab.com" && $CI_PROJECT_NAMESPACE == "gitlab-org" && $CI_MERGE_REQUEST_IID'
@@ -293,7 +293,7 @@
 ################
 .shared:rules:update-cache:
   rules:
-    - <<: *if-master-schedule-2-hourly
+    - <<: *if-default-branch-schedule-2-hourly
     - <<: *if-security-schedule
     - <<: *if-merge-request-title-update-caches
 
@@ -434,26 +434,26 @@
     - <<: *if-merge-request
       changes: *frontend-patterns
 
-.frontend:rules:ee-mr-and-master-only:
+.frontend:rules:ee-mr-and-default-branch-only:
   rules:
     - <<: *if-not-ee
       when: never
     - <<: *if-merge-request
       changes: *code-backstage-patterns
       when: always
-    - <<: *if-master-refs
+    - <<: *if-default-branch-refs
       changes: *code-backstage-patterns
 
 .frontend:rules:qa-frontend-node:
   rules:
-    - <<: *if-master-refs
+    - <<: *if-default-branch-refs
       changes: *frontend-dependency-patterns
     - <<: *if-merge-request
       changes: *frontend-dependency-patterns
 
 .frontend:rules:qa-frontend-node-latest:
   rules:
-    - <<: *if-master-refs
+    - <<: *if-default-branch-refs
       changes: *frontend-dependency-patterns
       allow_failure: true
     - <<: *if-merge-request
@@ -464,7 +464,7 @@
   rules:
     - <<: *if-not-canonical-namespace
       when: never
-    - if: '$DANGER_GITLAB_API_TOKEN && $CI_MERGE_REQUEST_IID && ($CI_MERGE_REQUEST_TARGET_BRANCH_NAME == "master" || $CI_MERGE_REQUEST_TARGET_BRANCH_NAME == "main")'
+    - if: '$DANGER_GITLAB_API_TOKEN && $CI_MERGE_REQUEST_IID && $CI_MERGE_REQUEST_TARGET_BRANCH_NAME == $CI_DEFAULT_BRANCH'
       changes: *frontend-patterns
       allow_failure: true
 
@@ -484,7 +484,7 @@
   rules:
     - <<: *if-not-ee
       when: never
-    - <<: *if-master-schedule-2-hourly
+    - <<: *if-default-branch-schedule-2-hourly
 
 ############
 # QA rules #
@@ -824,14 +824,14 @@
     - changes: *db-library-patterns
     - <<: *if-merge-request-title-run-all-rspec
 
-.rails:rules:ee-mr-and-master-only:
+.rails:rules:ee-mr-and-default-branch-only:
   rules:
     - <<: *if-not-ee
       when: never
     - <<: *if-merge-request-title-run-all-rspec
     - <<: *if-merge-request
       changes: *code-backstage-patterns
-    - <<: *if-master-refs
+    - <<: *if-default-branch-refs
       changes: *code-backstage-patterns
 
 .rails:rules:detect-tests:
@@ -887,7 +887,7 @@
   rules:
     - <<: *if-not-ee
       when: never
-    - <<: *if-master-schedule-nightly
+    - <<: *if-default-branch-schedule-nightly
     - <<: *if-merge-request-title-run-all-rspec
 
 .rails:rules:rspec-coverage:
@@ -897,7 +897,7 @@
     - <<: *if-merge-request
       changes: *code-backstage-patterns
       when: always
-    - <<: *if-master-schedule-2-hourly
+    - <<: *if-default-branch-schedule-2-hourly
     - <<: *if-merge-request-title-run-all-rspec
       when: always
 
@@ -905,21 +905,21 @@
   rules:
     - <<: *if-not-ee
       when: never
-    - <<: *if-master-schedule-2-hourly
+    - <<: *if-default-branch-schedule-2-hourly
       allow_failure: true
     - <<: *if-merge-request-title-run-all-rspec
 
-.rails:rules:master-schedule-nightly--code-backstage:
+.rails:rules:default-branch-schedule-nightly--code-backstage:
   rules:
-    - <<: *if-master-schedule-nightly
+    - <<: *if-default-branch-schedule-nightly
     - <<: *if-merge-request
       changes: [".gitlab/ci/rails.gitlab-ci.yml"]
 
-.rails:rules:master-schedule-nightly--code-backstage-ee-only:
+.rails:rules:default-branch-schedule-nightly--code-backstage-ee-only:
   rules:
     - <<: *if-not-ee
       when: never
-    - <<: *if-master-schedule-nightly
+    - <<: *if-default-branch-schedule-nightly
     - <<: *if-merge-request
       changes: [".gitlab/ci/rails.gitlab-ci.yml"]
 
@@ -945,7 +945,7 @@
   rules:
     - if: '$CODE_QUALITY_DISABLED'
       when: never
-    # - <<: *if-master-refs  # To be done in a later iteration: https://gitlab.com/gitlab-org/gitlab/issues/31160#note_278188255
+    # - <<: *if-default-branch-refs  # To be done in a later iteration: https://gitlab.com/gitlab-org/gitlab/issues/31160#note_278188255
     - <<: *if-default-refs
       changes: *code-backstage-patterns
       allow_failure: true
@@ -954,7 +954,7 @@
   rules:
     - if: '$SAST_DISABLED || $GITLAB_FEATURES !~ /\bsast\b/'
       when: never
-    # - <<: *if-master-refs  # To be done in a later iteration: https://gitlab.com/gitlab-org/gitlab/issues/31160#note_278188255
+    # - <<: *if-default-branch-refs  # To be done in a later iteration: https://gitlab.com/gitlab-org/gitlab/issues/31160#note_278188255
     - <<: *if-default-refs
       changes: *code-backstage-qa-patterns
       allow_failure: true
@@ -963,7 +963,7 @@
   rules:
     - if: '$DEPENDENCY_SCANNING_DISABLED || $GITLAB_FEATURES !~ /\bdependency_scanning\b/'
       when: never
-    # - <<: *if-master-refs  # To be done in a later iteration: https://gitlab.com/gitlab-org/gitlab/issues/31160#note_278188255
+    # - <<: *if-default-branch-refs  # To be done in a later iteration: https://gitlab.com/gitlab-org/gitlab/issues/31160#note_278188255
     - <<: *if-default-refs
       changes: *code-backstage-qa-patterns
       allow_failure: true
@@ -984,7 +984,7 @@
   rules:
     - if: '$DAST_DISABLED || $GITLAB_FEATURES !~ /\bdast\b/'
       when: never
-    - <<: *if-master-schedule-nightly
+    - <<: *if-default-branch-schedule-nightly
       allow_failure: true
 
 .reports:rules:license_scanning:
@@ -1118,13 +1118,13 @@
   rules:
     - <<: *if-not-canonical-namespace
       when: never
-    - <<: *if-master-or-tag
+    - <<: *if-default-branch-or-tag
       changes: *code-backstage-qa-patterns
       when: on_success
 
 .setup:rules:dont-interrupt-me:
   rules:
-    - <<: *if-master-or-tag
+    - <<: *if-default-branch-or-tag
       allow_failure: true
     - <<: *if-auto-deploy-branches
       allow_failure: true